Light conductors made of optic fibers for transmitting light can be used to transmit signals or light.
Patent DE 202008001786 describes an elevator installation in which optic fibers are used in the pull cables for positioning the elevator cabin or monitoring a carrier belt.
It can occur that the fiber bundles must be bent for a period of time, so that the light conductor can also transmit the light or signal to the desired location.
Prior art in general teaches methods for bending fiber bundles to conduct light. For example, according to the state of the art, the bending or reshaping of the fiber bundle is performed with the help of a curling wedge. After the bending process, the curling wedge usually remains in the bent fiber bundle and is cemented to it. There is the risk, however, that the curling wedge is not held firmly enough by the solidified cement and can come loose from the bonding of the cementing agent and fiberglass. This can be particularly disadvantageous when the optic fibers are used in a medical device. In the worst case, the released wedge can be discharged inside the patient.
If the curling wedge is removed from the bent fiber bundle after the bending procedure, it leaves a gap, which must be filled with cement. The additional application of cement into the gap can result in a poor bond between the cement and the fiber bundle. This can lead to variable adhesion levels in the fiber bundle, particularly when the cement migrates to locations in the fiber bundle that restrict the lengthwise extension of the fiber bundle from fluctuations in pressure and temperature and reduce the mechanical strength, as can occur for example in sterilization by autoclave. As a result of insufficient capacity for lengthwise extension, individual fibers in the fiber bundle can be broken.
According to an additional method for bending fiber bundles of light conductors, the bending or reshaping of the fiber bundle is performed by making use of the geometric structure of the section of the apparatus housing that is provided to encase the fiber bundle. The fibers in this case are bent with the help of corresponding guidance and reception sections in the apparatus housing. This demands a housing with complex structure, which can be challenging and expensive in terms of planning and manufacture. With this method, the optic fiber bundles are usually fastened in the housing structure by means of a cement, although here as well it is not possible to ensure whether the cement remains in the position foreseen for it or if it migrates disadvantageously to other locations by capillary action of the fiber bundle. This, again, can lead to unintended fastening at some locations in the fiber bundle, which can cause disadvantageous pulling, pressing and crosswise tensions in the fiber bundle, especially in autoclaving.